I can't save the game, if i do that, the game closes. On both games

I am sure it is a feature not a bug. the game apparently has two ways of saving, or two different menus.

If you use the up left icon and then press the main menu icon you can exit or load/save the game. Afterwards you can continue your game.
But if you press ESC in your keyboard it leads you to the exit menu where you can save, exit or cancel: Exit, quits the game without saving and Save saves your game but then it shuts down. I always considered it was a feature because it does not crash, just exits, and the game is saved accordingly.
At least that is my experience.

greetings

Yep, Gudadantza is correct. I remember encountering this when I played the games as well, until I finally figured out that pressing ESC in the Dark Sun games is actually the "Quit Game" menu, not the typical "Game Menu" you might expect from more modern games. XD

Use F1 to save and F2 to load.
If you use ESC to save it will quit after.

And use LSHIFT to skip the animations...

From the party menu, go to the Settings menu. Save without quitting. Hitting Escape and saving will exit the game. Long after I figured this out, I was still hitting Escape out of routine and feeling like a moron.

To add to that:

Even if you accidentally hit escape, go into the save menu there, realize your mistake and go back.
It'll still remember you tried, and the next time you save via F1 it'll quit the game after.
I think this also causes other crashes eventually.

This only happens if you open the save menu via escape, opening the escape menu itself and then closing it is harmless.